Growth of Cd1-xMnxTe crystals by vertical Bridgman method and analysis of composition dependence on the bandgap

• Published in: Materials science in semiconductor processing 2023-08, Vol.162, Article 107484
• Main Authors: Rajan, Manivel, Paulraj, Rajesh, Palanimuthu, Vijayakumar, Ganesan, K, Roy, Varsha, Amaladass, Edward Prabu, Sarguna, R.M., Ganesamoorthy, S., Perumalsamy, Ramasamy
• Format: Article
• Language: English
• ISSN: 1369-8001; 1873-4081
• DOI: 10.1016/j.mssp.2023.107484

This article reports the growth of cadmium manganese telluride (Cd1-xMnxTe, CMT) single crystal by vertical Bridgman method and the property measurements for three different Mn compositions (x = 0.05, 0.10 & 0.15). The single crystalline nature of the grown crystals was confirmed with Laue back reflection method. The lattice constants were calculated using single-crystal X-ray diffraction analysis. Phase formation and zinc blende crystal structure were confirmed with powder X-ray diffraction analysis. The shifting of the diffraction peak position indicates the reduction in lattice parameter of Cd1-xMnxTe crystals with Mn concentration. Raman spectra exhibited two mode behavior having CdTe and MnTe-like structures and their longitudinal optical phonon modes displaying peak shift with Mn concentration. The increase in the Mn concentration in CMT lattice made a blueshift in photoluminescence emission band leading to changes in the bandgap from 1.5776 to 1.7250 eV. The experimentally observed IR transmittance was found to be in line with theoretically observed transmittance. The observed Mn concentration dependent structural and optical properties confirm the formation of high quality CMT single crystals by vertical Bridgman technique. [Display omitted] •Cd1-xMnxTe single crystals with Mn concentrations 0.05, 0.10 & 0.15 were grown using an optimized homemade furnace.•The structural confirmation and change in lattice parameters as a function of manganese concentration were observed and explained.•The FTIR transmittance of the CMT wafers shows a higher transparency than the theoretical value of 60%.•The increase in bandgap with the increase in Mn concentration proved with PL measurements and it perfectly matches the theoretical values.•The measured PL peak positions and the PL mapping values are the same as each other.